CVE-2026-3298
Windows-only buffer overflow in asyncio ProactorEventLoop.
Is CVE-2026-3298 being exploited?
Not confirmed. CVE-2026-3298 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.39% probability of exploitation in the next 30 days.
How severe is CVE-2026-3298?
CVE-2026-3298 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-3298?
Not known from our data. No patch reference has been recorded for CVE-2026-3298, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-3298 affect?
CVE-2026-3298 affects Windows Python (asyncio ProactorEventLoop). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-3298?
Patch when released; test Windows apps first
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Out-of-bounds write via sock_recvfrom_into() could crash or memory-corrupt Windows apps.
Patch when possible
- affected< 3.11.16
- affected>= 3.12.0 and < 3.12.14
- affected>= 3.13.0 and < 3.13.14
- affected>= 3.14.0a1 and < 3.14.5rc1
- affected>= 3.15.0a1 and < 3.15.0b1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.